Debian Administration Training Course

Debian Distribution

What is Debian?

• Selecting the appropriate Debian version
• Accessing Debian support and resources
• Navigating the Debian community

Console Fundamentals

• Understanding the shell prompt
• Configuring the shell prompt within the X environment
• Managing the root account and root shell prompt (using su, sudo, and running programs as root under X)
• Utilizing GUI system administration tools
• Navigating virtual consoles
• Exiting the command prompt correctly
• Shutting down the system properly
• Restoring a functional console
• Recommended additional packages for beginners
• Creating an additional user account
• Configuring sudo

The Filesystem

• Understanding filesystem permissions
• Controlling permissions for newly created files via umask
• Managing permissions for user groups
• Working with timestamps
• Creating and managing links
• Utilizing named pipes (FIFOs)
• Understanding sockets
• Working with device files
• Understanding special device files
• Exploring procfs and sysfs

Midnight Commander (MC)

• Customizing MC
• Launching MC
• Navigating the file manager in MC
• Advanced command-line techniques in MC
• Using the internal editor in MC
• Using the internal viewer in MC
• Configuring auto-start features of MC
• Utilizing MC's FTP virtual filesystem

The Basic Unix-like Work Environment

• Understanding the login shell
• Customizing bash
• Using special keystrokes
• Navigating the pager
• Setting a default text editor
• Exiting vim
• Recording shell activities
• Mastering basic Unix commands

Basic Shell Commands

• Command execution and environment variables
• Understanding the "$LANG" variable
• Understanding the "$PATH" variable
• Understanding the "$HOME" variable
• Utilizing command line options
• Using shell globbing
• Checking the return value of a command
• Executing typical command sequences and shell redirection
• Creating command aliases

Unix-like Text Processing

• Utilizing Unix text tools
• Working with regular expressions
• Using replacement expressions
• Performing global substitution with regular expressions
• Extracting data from text file tables
• Writing script snippets for piping commands

Debian Package Management

Prerequisites for Debian Package Management

• Configuring packages
• Observing basic precautions
• Managing continuous upgrades
• Understanding Debian archive basics
• Understanding package dependencies
• Understanding the lifecycle of package management
• Initial troubleshooting for package management issues

Basic Package Management Operations

• Comparing apt-get/apt-cache with aptitude
• Performing basic package management operations via the command line
• Using aptitude interactively
• Using key bindings in aptitude
• Navigating package views in aptitude
• Search method options with aptitude
• Understanding the aptitude regex formula
• Resolving dependencies with aptitude
• Reviewing package activity logs

Examples of aptitude Operations

• Listing packages with regex matching on package names
• Browsing using regex matching
• Completely purging removed packages
• Cleaning up auto/manual installation status
• Performing a system-wide upgrade

Advanced Package Management Operations

• Performing advanced package management operations via the command line
• Verifying installed package files
• Precautions for package issues
• Searching package metadata

Internals of Debian Package Management

• Understanding archive metadata
• The top-level "Release" file and its authenticity
• Archive-level "Release" files
• Fetching metadata for packages
• Understanding package states for APT
• Understanding package states for aptitude
• Managing local copies of fetched packages
• Understanding Debian package file naming conventions
• Using the dpkg command
• Using the update-alternatives command
• Using the dpkg-statoverride command
• Using the dpkg-divert command

Recovery from a Broken System

• Addressing incompatibility with old user configurations
• Handling overlapping files between different packages
• Fixing broken package scripts
• Rescuing the system with the dpkg command
• Recovering package selection data

Tips for Package Management

• Selecting appropriate Debian packages
• Managing packages from mixed archive sources
• Adjusting candidate versions
• Handling Updates and Backports
• Automating package download and upgrade processes
• Limiting APT download bandwidth
• Performing emergency downgrades
• Identifying package uploaders
• Utilizing the equivs package
• Porting packages to stable systems
• Configuring APT proxy servers
• Managing small public package archives
• Recording and copying system configurations
• Converting or installing alien binary packages
• Extracting packages without using dpkg
• Further reading for package management

System Initialization

• Overview of the bootstrapping process
• Understanding BIOS, boot loaders, and mini-Debian systems
• Understanding runlevels
• Configuring runlevels
• Examples of runlevel management
• Default parameters for each init script
• Configuring the hostname
• Configuring the filesystem
• Initializing network interfaces
• Initializing network services
• Understanding system messages
• Understanding kernel messages
• Working with the udev system
• Initializing kernel modules

Authentication and Security

• Standard Unix authentication
• Managing account and password information
• Creating strong passwords
• Generating encrypted passwords
• Understanding PAM and NSS
• Configuration files accessed by PAM and NSS
• Modern centralized system management
• Understanding "Why GNU su does not support the wheel group"
• Implementing stricter password rules
• Configuring other access controls
• Using sudo
• Utilizing SELinux and Apparmor
• Restricting access to specific server services
• Ensuring authentication security
• Sending passwords securely over the Internet
• Using Secure Shell
• Implementing extra security measures for the Internet
• Securing the root password

Network Setup

Basic Network Infrastructure

• Understanding domain names
• Configuring hostname resolution
• Understanding network interface naming
• Defining the network address range for LAN
• Ensuring network device support

Modern Network Configuration for Desktops

• Using GUI network configuration tools

Low-Level Network Configuration

• Using iproute2 commands
• Performing safe low-level network operations

Network Optimization

• Identifying optimal MTU
• Setting MTU
• Optimizing WAN TCP

Netfilter Infrastructure

Network Applications

The Mail System

• Basics of modern mail services
• Mail configuration strategies for workstations

Mail Transport Agent (MTA) and Mail User Agent (MUA)

• Overview of exim4
• Basic MUA - Mutt

Mail Delivery Agent (MDA) with Filters

• Configuring maildrop
• Configuring procmail
• Redelivering mbox contents

POP3/IMAP4 Servers

Remote Access Server and Utility (SSH)

• SSH fundamentals
• Port forwarding for SMTP/POP3 tunneling
• Connecting without remote passwords
• Handling incompatible SSH clients
• Setting up ssh-agent
• Shutting down remote systems via SSH
• SSH troubleshooting

Other Network Application Servers

Other Network Application Clients

Diagnosing System Daemons

The X Window System

• Setting up the desktop environment
• Understanding the server/client relationship
• Configuring the X server
• Starting the X Window System
• Starting X sessions with gdm
• Customizing X sessions (classic method)
• Customizing X sessions (new method)
• Connecting remote X clients via SSH
• Securing X terminals over the Internet
• Utilizing X applications
• Using X office applications
• Using X utility applications

System Tips

The screen Program

• Use cases for screen(1)
• Key bindings for the screen command

Data Recording and Presentation

• Using the log daemon
• Using log analyzers
• Cleanly recording shell activities
• Customizing text data display
• Customizing time and date display
• Colorized shell echo
• Colorized commands
• Recording editor activities for complex repeats
• Recording the graphic image of an X application
• Recording changes in configuration files

Data Storage Tips

• Configuring disk partitions
• Accessing partitions using UUID
• Configuring filesystems
• Creating filesystems and checking integrity
• Optimizing filesystems via mount options
• Optimizing filesystems via superblock
• Optimizing hard disk performance
• Using SMART to predict hard disk failure
• Expanding usable storage space via LVM
• Expanding usable storage space by mounting another partition
• Expanding usable storage space using symbolic links
• Expanding usable storage space using aufs

Data Encryption Tips

• Encrypting removable disks with dm-crypt/LUKS
• Encrypting swap partitions with dm-crypt
• Automatically encrypting files with eCryptfs
• Automatically mounting eCryptfs

Monitoring, Controlling, and Starting Program Activities

• Timing a process
• Setting scheduling priority
• Using the ps command
• Using the top command
• Listing files opened by a process
• Tracing program activities
• Identifying processes using files or sockets
• Repeating a command at constant intervals
• Repeating a command while looping over files
• Starting a program from the GUI
• Customizing program startup settings
• Killing a process
• Scheduling single tasks
• Scheduling recurring tasks
• Using the Alt-SysRq key

System Maintenance Tips

• Monitoring system users
• Alerting all users
• Identifying hardware
• Configuring hardware
• Managing system and hardware time
• Configuring the terminal
• Configuring the sound infrastructure
• Disabling the screen saver
• Disabling beep sounds
• Monitoring memory usage
• Performing system security and integrity checks

The Kernel

• Configuring kernel parameters
• Understanding kernel headers
• Compiling the kernel and related modules
• Compiling kernel source: Debian standard method
• Compiling module source: Debian standard method
• Utilizing non-free hardware drivers

Virtualized Systems

• Utilizing virtualization tools
• Understanding the virtualization workflow
• Mounting virtual disk image files
• Using chroot systems
• Managing multiple desktop systems

Data Management

Sharing, Copying, and Archiving

• Using archive and compression tools
• Using copy and synchronization tools
• Archive idioms
• Copy idioms
• File selection idioms
• Backup and recovery strategies
• Backup utility suites
• Example script for system backup
• Example script for data backup
• Managing removable storage devices
• Sharing data via network
• Archive media options

Binary Data

• Viewing and editing binary data
• Manipulating files without mounting disks
• Understanding data redundancy
• Data file recovery and forensic analysis
• Splitting large files into smaller files
• Clearing file contents
• Creating dummy files
• Erasing an entire hard disk
• Erasing unused areas of a hard disk
• Undeleting deleted but still open files
• Searching for all hardlinks
• Identifying invisible disk space consumption

Data Security Infrastructure

• Key management for GnuPG (signing and encrypting)
• Using MD5 sums